1. Field Of The Invention
The invention relates to a new process for the production of 7-acylindoles of the general formula: ##STR5## wherein R means a C.sub.1 -C.sub.4 -alkyl-, C.sub.2 -C.sub.4 -alkenyl-, C.sub.2 -C.sub.4 -alkinyl-, aryl- or heteroaryl group, starting from indoline of the formula: ##STR6##
2. Background Art
A process for the production of 7-acylindoles starting from indoline is known [Walsh et al., J. Med. Chem., Vol. 27, No. 11, (1984), pp. 1379 to 1388].
In the process indoline is first converted with a halogenated benzonitrile as an acylation agent into 7-acylindoline, which is then thermally dehydrogenated in the presence of manganese(IV)-oxide to 7-acylindole. A great drawback of the process is that, on the one hand, the feedstocks (the halogenated benzonitrile) are difficult to obtain chemically and, on the other hand, the process is feasible neither ecologically nor on a large scale.